In general, network elements include computing and storage devices, communication devices, software residing on these devices, etc. Examples are computes, disk storages, routers, switches, LANs, WANs, servers, and application software. Each element typically has a number of characteristics, or management variables, indicating its operating status. The management variables of an element are generally monitored so that problems occurring in the element can be detected and resolved. One approach for monitoring the elements is by polling. That is, a poller periodically gathers current status from the element being monitored. The gathered data is then sent to a processing unit that determines whether a problem has occurred in the element, and if so, a notification is generated.
Every network element provides a protocol for the poller to read and write its management variables. These variables are usually defined by vendors of the elements, and are usually referred to as a Management Information Base (MIB). There are some standard MIB's, such as the IETF (Internet Engineering Task Force), MIB I and MIB II. Through the reading and writing of MIB variables, software in other computers can manage or control the element. The software in other computers is usually called an agent. Thus, a network manager who is charged with the responsibility of locating and resolving network problems usually uses MIBs variables and agents to gather information from the elements.
Unfortunately, there is not a uniform MIB that can be used to manage a network consisting of elements supported by different vendors. Every MIB from every vendor uses a different set of messages to announce a network event, e.g. a fault. In general, these messages use a widely adopted messages format, known as a Simple Network Management Protocol (SNMP) trap. A network manager generally has to manually configure every element to generate SNMP traps properly. Even after traps are properly generated, there is rarely consistency in what each represents across different types of elements.
In addition, the amount of data that is retrieved by the pollers can be overwhelming in volume. This volume of data can present a serious problem to the network administrator who needs to decipher the true significance of all of the information.